mdiamondstone

authorGrid is a sidebar widget that displays the avatar of any author on your blog with at least one published post in grid form. You 
can set how large the avatar should be, how many columns (or rows) you’d like in the grid, and the display title of the widget.

Author Grid

Sidebar widget that displays the avatar of all of the authors on your blog in grid form.

BuddyDev

Brajesh Singh

shanebp

BP Local Avatars is a BuddyPress plugin.
Do you have members or groups on your BuddyPress site who do not have an Avatar? 
And you do not want to show the generic default avatar? 
Or maybe you do not want each page view to include a lot of calls to gravatar.com to load avatars?
<ul>
<li>This plugin will create a Gravatar Identicon avatar, thumb and full versions, for any user who does not already have an Avatar, and save it locally.</li>
<li>Supports user creation, user registration, user login, and Bulk Generation for user and groups.</li>
<li>Uses the existing BuddyPress avatar directory structure.</li>
<li>Conforms to the defined sizes for BuddyPress thumb and full avatars.</li>
<li>Users can still upload an avatar via their profile.</li>
<li>Groups can still upload an avatar via Group > Manage > Photo.</li>
</ul>
Usage:
<ol>
<li>
Provides an option in wp-admin under: 
Settings -> Discussion > Default Avatar > BuddyPress Identicon (Generated and Stored Locally).
</li>
<li>
Select and Save. Otherwise this plugin will not do anything.
</li>
<li>
After saving, you will see a link to ‘Bulk Generate’ avatars for all users and groups who do not have a local avatar. If a user already has their own Gravatar, it will save it locally.
</li>
</ol>
For more BuddyPress plugins, please visit <a href="https://www.philopress.com/" rel="nofollow ugc">PhiloPress</a>

BP Local Avatars

A BuddyPress plugin that creates Gravatar avatars for any user or group without one, and stores them locally.

Author Grid vs BP Local Avatars